Sodium benzoate is a safe, economical preservative commonly used preparations such as creams, lotions, gum solutions, and toothpaste. The advantages of sodium benzoate in these applications are that it is colorless, odorless, readily soluble, and generally is compatible other ingredients. It is most effective when used at a pH between 2.0 - 4.5 and the following maximum usage rates are recommended: Rinse off products: 2.5% Leave on products: 0.5%